In many applications in which certain materials are used in the fabrication of electrical connectors, for example, a need has arisen for more stringent requirements so as to provide better reliability and longer life at reasonable cost. For example, the rapid growth of the information and communications industries over the past decade has led to an increased use of "edge-card" connectors in both computers and other instruments. Such connectors are inserted and removed many times during the course of their life and in addition are usually subject to small amplitude oscillatory motions (sometimes referred to as "fretting") during use. Such operations cause the contact surfaces of such connector to wear and in the course thereof minute wear particles of the surface material are generated, most or all of which particles are retained in the region between the surfaces of the connector elements.
Over the course of time such wear particles will oxidize as the sliding and/or fretting motions continue. As a result the sliding surfaces of the connector tend to become separated by the oxidized, electrically insulative particles and the contact resistance between the connector elements is increased to levels above generally acceptable values. When this occurs, the resistance also tends to fluctuate widely which in turn creates spurious noise.
It is desirable, therefore, to design electrical connectors which overcome the contact resistance problems which arise because of the generation of wear particles during use and to provide such connectors at a reasonable cost.